Shaving device



Patented Feb. 18, 1941 UNITED STATES PATENT, OFFICE 5 Claims.

This invention relates to improvements in shaving devices, andhas for a principal object, the provision of an improved form of cutter head comprising an outer shear plate and an inner cutter member movable transversely with respect thereto and involving more particularly improvements in the cutter bar portions of the outer shear plate.

In certain types of existing shear plates, substantially heavy end members are provided and the cutter bars are formed of slots on'either side of a central portion or web which is normally secured to or formed integral with said heavy end members. art, the flexing of the active portions of the'shear plate is almost prevented, in fact the heavy end members are provided to prevent flexing. However, flexing does occur when the device is pressed against the skin and this flexing is the maximum in the center of the shear plate, decreasing in either direction toward the heavy end members. As .the inner cutter member is substantially rigid, this central flexing actually pushes the inner cutter memberaway from cutter bar portions on either side of the center.

An. object of the present invention is to provide an improved shear plate in which the cutter bar portions are not prevented from flexing.

A further object of the invention is the provision of a shear plate having a plurality of cutter bars and having heavy end members, said cutter bars being joined together by a central web which web is'unattached to said heavy end members, thereby permitting said cutter bars to flex in concert when pressure is applied thereto. I More detailed objects of the invention will be apparent from the following specification.

Referring to the drawing:

Figure l is'a part of a side elevation having portions thereof broken away to more specifically illustrate the new and improved structure; r

Figure 2 is a vertical transverse sectional view taken along the'line 2-2 of Figure 1;

Figure 3 is an enlarged detailed side elevational view of a portion of one end of the new and. improved cutter head or shear plate;

Figure 4 is a view of the portion shown in Figure 3 as viewed from above;

Figure 5 is a side elevational view, partly broken away, of a modification of the cutter head shown in Figure 1;

Figure 6 is an enlarged end elevation of the modified cutter head shown in Figure 5;

By such construction in the prior Figure '7 is an enlarged detailed side elevational view of a portion of one end of the cutter head shown in Figure 5;

Figure 8 is a top view of a portion of one end of the cutter head shown in Figure 5;

Figure 9 is a diagrammatic sketch depicting the flexing occurring in devices of the prior art previously referred to; and

Figure -10 is a diagrammatic sketch depicting the flexing occurring in my new and improved shear plate. t

In dry shaving devices of the type herein disclosed, the outer shear plate, which is commonly slotted to provide a plurality of cutter bars, is applied at its outer face to the surface of the skin, and the inner cutter which operates in back of the shear plate against the rear face of the cutter bars therein. The hairs to be clipped enter the slots and are cut off at the rear edges of the cutter bars of the outer shear plate. It is at once apparent, therefore, that the thickness of the outer shear plate at the cutter bars, in part at least, determines how close the hairs are cut off to the surface of theskin. The cutter bars are therefore of necessity made extremely thin with the result that they are physically weakened. The central object of this invention is to provide an improved construction of the cutter bars of the outer shear plate where portions of the active lengths thereof are made much thinner without rendering them impractical, the central rib or web formed integral with said cutter bars, serving to cause said cutter bars to flex in'concert when pressed against the user's skin. The central rib or web is not attached to the heavy end members of the shear plate, as is the case in similar devices of the prior art. Referring to the drawing, at I is shown the upper end of the usual handle casing which houses the motor for operating the device. As shown, the upper end of there-sing is grooved as indicated at 2 to receive the cutter head assembly. The cutter head assembly is locked in the groove by a set screw (not shown) and positioned therein by a pin, {mounted in the casing so as to engage a recess in the cutter head. The cutter head comprises an outer mem-' her 4 which may be made from a solid block of suitable steel, or formed up in other ways, as is known in the art, to provide a hollow upper section having a relatively thin wall 6. The wall 6 is bounded at each end thereof by substantially heavy semi-circular portions 5, 5a. -A plurality of transverse slots 1 are formed in and extend through the wall 6 and said slots extend outwardly and away from a central portion 8 which forms a continuous band or web extending longitudinally along the upper face of the wall 6 from a point adjacent to the heavy end portions 5 and 5a, the band or web 8 being separated from said ends 5, 5a by slots 22 and 23.

Aligned with the slots I and extending further down both sides of the wall 5, are a series of wider slots 9 which are concentric with the slots I. These sets of aligned slots 1 and 9 on opposite sides of the wall, 6 as is clear from Figures 2 and 4, form cutter bars III, at the active portion, which forms what is commonly termed the outer shear plate. The thickness of the bars l0 and the strip 8 are reduced to a degree of thinness such as is illustrated in Figure 2, some portions of the cutter bar being of uniform thinness and other portions of increasing cross section away from the center towards the ends of the parts, as viewed in Figure 2, thereby providing a relatively strong cutter bar ID of extremethinness and due to the fact that the central portion 8 is a band or web joining all of the cutter bars I0 together along the mid line, said cutter bars may flex in concert when pressure is applied thereto by the skin of the user.

The slots I, as stated above, are aligned with wider slots 9 so that in effect each slot 1, 9, comprises a stepped slot. The wide portion 9 permits easy entry of the hair and facilitates the guiding of the hair to and into the narrow portions 1 where they may be cut.

The inner cutter I4 is made in the form of a hollow cylinder and the central opening or hole 24 extending therethrough may be either circular or polygonal, and may either be concentric withthe outer diameter of the cutter H or may be eccentric thereto. The inner cutter is provided with a series of transverse slots 16 forming therebetween cutter bars l5 which when the device is assembled and operated, cooperate with the cutter bars W to shear or cut hair. One end of the inner cutter member I4 is slotted, as indicated at H, to cooperate withand be engaged by the head iii of a pin mounted in the member 4 to guide and insure rectilinear reciprocation of the inner cutter. In some instances, the sides of the inner cutter near the ends of the slots l6 may be ground away or undercut, as indicated at I9 to reduce the frictional resistance to the movement of the inner cutter.

A lever 20 oscillated by a motor (not shown) engages a slot 25 formed in the outer wall of the inner cutter member l4 preferably near the midpoint thereof opposite the cutter bars l5.

A pair of spring loaded pins 2| and 26 engage depressions 21 and 28 respectively formed in the inner cutter member I4 and maintain the outer surfaces of the cutter bars l5 in intimateshearing contact with the inner faces of the cutter I the flexing action is illustrated diagrammatically.

Contrasted with this the diagram Figure 9, which is a diagrammatic representation of those types of devices of the prior art in which the central web connecting the cutter bars is also connected to the heavy end portions, shows the flexing action in which the heavy end portions resist the flexing and tend .to stiffen the whole structure. It, may be readily seen that flexing, which is bound .to occur no matter how rigid the construction, is maximum in the midportion, diminishing 1 as each end is approached. Therefore, the inner cutter member, which is substantially rigid, is in intimate shearing contact only in the midportion.

In the modification shown in Figures 5-8 in- 1 clusive, the cutter head assembly comprises a base member 30 which may be made from asolid block of suitable steel and having secured there to a sheet 3| of suitable stock formed up in the manner illustrated, and having side portions per- 2 manen-tly secured to the base 30. The sides 3m and 3lb are preferably straight and terminate in a curved portion spanning the inner cutter member 32 (see Figure 6). The curved portion above referred to is at each end thereof reinforced to form heavy guards, one of which is shown in Figure 7 and designated by the numeral 33. A band or web 36 extends longitudinally of the cutter head and has its central axis substantially in line with the central axis of the cutter head. 3 Two series of slots 34, one on each side of said web 36 extend across the curved face of the cutter head and extend downwardly in the side portions 3|a, (ill: to points adjacent to the base The solid portions between the slots 34 form cutter bars and are designated by the numeral 35.

Perforations 31 formed in the web 36 also form shearing edges.

Near each end of the cutter head and adjacent 4 to'the heavy guards 33 are formed the slots 40 which extend from a point adjacent to the base 30 in the wall 31a, upwardly across the curved portion and downwardly in the wall 3|b to a point adjacent to the base 30, thereby completely 4 severing the web 36 from the heavy end guards 33, and permitting the cutter bars 35 to flex in concert when the cutter head is pressed against the skin.

The base 30 has formed therein holes 38 and 5 39 through which spring-loaded plungers such as those shown at 2| and 26 in Figure 1, may extend, to resiliently engage the inner cutter member 32 and hold its cutter bars 4! in intimate contact with the cutter bars 35. A central hole 4 42 is provided in base 30 through which a driving lever such as the lever 20 shown in Figure 1, may extend, for driving the inner cutter member through the medium of a slot such as the slot 25 shown inFigure 1. 1

A slot 43 is provided in the base 30 to engage a projection or locating member (not shown) carried on the motor casing and a depression 44 formed in the face of the Wall 3lb is provided to be engaged by a screw or other suitable fastening means carried on the motor housing (not rigid flexibility which at all times insures intimate shearing contact between the outer surfaces of the cutter bars on the inner cutter mem-. ber and the inner surfaces of the outer cutter bars.

Due to the presence of. the strips 8 and 36, it is unnecessary to hold the cutter bars against flexing by means of the inner cutter member, an

expedient employed in Patent No. 1,721,530. .to

Schick. In; said patent, the inner cutter member is inflexibly held by adjustable set screws so that it positively supports the cutter bars of the outer guard against being flexed.

Contrasted with this, the main object of the present invention is to have the outer cutter bars flex when the device is pressed against the skin.

Therefore, a desired degree of rigid flexibility is imparted to the outer cutter bars in accordance with the present invention, the inner cutter member being resiliently held against the interior of the active cutting area of the outer cutter bars,

departing from the spirit of the invention as set.

forth in the following claims.

What is claimed is? 1. In-a shaving device, an outer shear plate carrying rigid end guards and a structure therebetween discontinuous with said end guards. said structure comprising a plurality oi flexible cutter bars having slots therebetween, and a rib or web extending on a mid-line along said structure and joining said cutter bars together to impart thereto a degree of rigid flexibility sum.- cient to cause said bars to flex in concert when deformed by external pressure.

2. In a shaving device, an outer shear plate including a metallic block forming a base, a. preformed metallic sheet secured to said base and forming an outer shear plate, a rigid end guard formed at each end of said shear plate, and a- 'structure therebetween discontinuous with said end guards and comprising a plurality of flexible cutter bars having slots therebetween, and a longitudinal web formed integral with said outter bars and imparting to said bars a degree of rigiditymaking special support for them unnecessary and a degree of flexibility suflicient to permit said bars to flex in concert when deformed by pressure against the users skin.

3. A head for shaving devices comprising in combination an outer shear plate having at each end thereof substantially heavy guard members,

a plurality of series of slots in said plate, one

series being on each side of a central longitudinal web, the solid portion between said slots forming cutter bars, and a slot adjacent to each end of said shear plate between said end guard members and said cutter bars'severing said web from said heavy end guards thereby permitting said cutter bars to flex in concert when pressed against the skin, and an inner cutter resiliently mounted for reciprocable movement across the inner faces of said cutter bars, said inner cutter member being slotted to form cutter bars adapted to cooperate with said first cutter bars.

4. In a' shaving device, an outer shear plate carrying rigid end guards and a structure therebetween comprising a perforated longitudinal rib orweb extending from end to. end of said structure, a plurality of flexible cutter bars having slots therebetween, said cutter bars lying in planes angular with respect to and tied together by said web, and end slots at each end of said structure separating said structure from said rigid end guards.

5. The invention according to claim 4 in which said end slots are longer than the slots between said cutter bars, thereby further isolating said structure from the rigidity of said rigid end guards.

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